What Is GSM in Corrugated Boxes?
GSM stands for grams per square metre. It is the weight of one square metre of the paper used in the board. Higher GSM paper is thicker and stronger, so the box takes more load and costs more. Most Indian corrugated boxes use papers roughly between 100 and 250 GSM, chosen layer by layer.
Why GSM matters to a buyer
Two boxes can look identical and perform very differently, and GSM is usually the reason. The paper weight in each layer decides how the box handles compression, punctures and repeat handling. When a supplier quotes a rate, the GSM of each layer is a large part of that number, so comparing quotes without comparing GSM is comparing nothing.
Common ranges in Indian units
| Layer | Commonly used range | What it does |
|---|---|---|
| Outer liner | Roughly 120 to 250 GSM | Takes printing, resists scuffing |
| Fluting (middle) | Roughly 100 to 150 GSM | Cushioning and rigidity |
| Inner liner | Roughly 100 to 180 GSM | Protects the product side |
These are working ranges, not rules. A unit will mix layers to hit the strength you need at a sensible cost. Heavier product, higher GSM on the liners. Long storage in humid months, a step up across the board.
How to specify GSM without guesswork
- Tell the manufacturer the packed weight and how the box travels. Let them propose the GSM mix.
- Ask for the GSM of each layer in writing on the quote, not just the ply.
- For repeat orders, keep the approved GSM spec on record so every batch matches the first.
Frequently asked questions
Is higher GSM always better?
It is stronger, but past the point your load needs, extra GSM only adds cost and weight. Match GSM to the job.
Does GSM affect printing?
Yes. A heavier, smoother outer liner holds print better, which matters for branded cartons.
How is GSM checked?
Units check it at paper intake by weighing a cut sample of known area. Ask whether your supplier verifies incoming paper.